SAJ Solar Batteries – Flexible, High-Voltage, Scalable Energy Storage
SAJ is a company offering lithium battery storage systems designed for home and commercial solar installations. Their batteries are built with LiFePO₄ chemistry, modular designs, and safety, making them suitable for both indoor and outdoor use.
Key Models / Series & What They Offer
Here are the main battery/energy storage series from SAJ and what capacities/features they include:
B2 Series (High-Voltage / HV)
Modular battery pack built with LiFePO₄ cells (cobalt-free).
Usable capacities scalable from roughly 5.12 kWh up to ~25.6 kWh depending on how many modules (1 to 5) are stacked.
Rated energy (before usable deductions) closely follows those values; usable is slightly less (because of depth-of-discharge limits).
Nominal voltage ranges vary with module count: from ~102.4V (for one module) up to ~512V (for five modules).
Designed with sheet-metal shell and stacking/wall-mount compatibility.
B2 Series (Low-Voltage / LV)
Similar modular and LiFePO₄ chemistry but designed for lower-voltage setups or systems that require LV compatibility.
Flexible number of modules, stacking allowed; allows for up to ~25 kWh storage in LV format.
Built with safety, compactness, and modular expansion in mind.
HS2 Series (All-in-One Hybrid Systems)
These systems combine battery + inverter (so it’s an integrated solution).
Available in different configurations: single-phase and three-phase models.
Power ratings vary depending on model – for example, some 3-6 kW for single-phase, and larger for three-phase.
Usable capacity is scaled depending on number of battery modules and phase type.
Technical Specifications & Performance
Here are some of the key technical features and performance specs that make SAJ batteries strong choices:
Battery Chemistry: Lithium Iron Phosphate (LiFePO₄), which offers better safety, longer cycle life, and thermal stability.
Depth of Discharge (DoD): Typically around 90% usable capacity in many of their models. Some hybrids or HV systems have DoD over 90-plus percent.
Scalability / Modularity: You can connect multiple modules (up to 5) in B2 series to meet larger energy storage requirements.
Voltages & Current: Depending on modules, nominal voltage ranges from ~100-110V up to ~500-V+ in high-voltage setups. Maximum charge/discharge currents like ~30 A are common in many modules.
Usable vs Rated Energy: While rated (or nominal) stored energy might be 5.12-25.6 kWh in some pack sizes, usable energy is somewhat less depending on discharge limits, usually in the ballpark of ~90% of rated.
Build & Protection: Many modules have IP65 rating (dust/water resistant), natural convection cooling (no loud fans), wall-mount or floor/ground-mount options. Battery packs often include a Battery Management System (BMS) with protection for over/under voltage, over/temperature, safety features
Advantages & Ideal Use-Cases
Here are what SAJ batteries do particularly well, and situations where they make sense:
Supports backup power in blackouts (with the correct inverter system).
Good for homeowners who want to start with modest storage (one module) and expand later.
Ideal in systems where you want high usable energy, high voltage compatibility (for efficient energy conversion), or hybrid inverter setups.
Outdoor installation is feasible (weather-rated enclosures), so flexibility in mounting.
Modern safety features and LiFePO₄ chemistry help with longevity and reliability.